Celtic will owe Benfica 30 per cent of any future transfer fee for Jota, according to a report in Portugal.
Ange Postecoglou 's side are on the brink of making his loan move permanent after a stunning season on loan.
Jota has lit it up with 12 goals and 12 assists – helping fire Celtic to the verge of the Premiership title.
He scored in the draw with Rangers at the weekend that means the Parkhead side need a maximum of four points from their last three games to secure the crown.
They hold an option to buy for £6.5m and it's believed they are in advanced talks to trigger that with the winger keen on staying put.
But it seems it's more than just a flat fee as Portuguese outlet A Bola are reporting Benfica have put assurances in place over a future deal.
They say his current parent club will bank 30 per cent of any future transfer should Celtic cash in on him down the line.
It's Benfica's way of ensuring they don't miss out entirely on a big payday if Jota fulfils his potential at Celtic Park.
Such a move is common practice nowadays with Celtic themselves often earning further windfalls through sell-on clauses after the transfer of players.
